Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsLinear ICsDS34T108GN+

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Note 6:

The 1F capacitor in series with TTIPn is only necessary in G.703 2048kHz mode (LTISR.TX

G703=1).

Note 7: The 560pF on TTIPn/TRINGn must be tuned for your application.

Note 8: Resistor R

is not necessary if receiver termination is internal. See LRISMR.RIMPM[2:0].

Table 10-60. Transformer Specifications

Specification Recommended Value

Turns Ratio, 3.3V Applications 1:1 (Rx) and 1:2 (transmit) ±2%

Primary Inductance

600H minimum

Leakage Inductance

1.0H maximum

Intertwining Capacitance 40pF maximum

Transmit Transformer DC Resistance

Primary (Device Side)

Secondary

1.0 maximum

2.0 maximum

Rx Transformer DC Resistance

Primary (Device Side)

Secondary

1.2 maximum

10.13.1

LIU Operation

The incoming analog AMI/HDB3 waveform (E1) or analog AMI/B8ZS waveform (T1) is transformer coupled into the

RTIP/RRING pins of the LIU receiver. The LIU can be config

ured for internal termination (software selectable for

75, 100, 110 or 120 applications) or external termination. The LIU receiver recovers clock and data from the

incoming analog signal and passes it through the jitter attenuation mux. The receiver contains an active filter that

reconstructs the analog received signal for the nonlinear losses that occur in transmission. The receiver circuitry is

configurable for various monitor applications. The device has a usable Rx sensitivity of 0dB to -43dB for E1 and

0dB to -36dB for T1, which allows the device to operate on 0.63mm (22AWG) cables up to 2.5km (E1) and 6k feet

(T1) in length. Data input to the LIU transmitter is sent via the jitter attenuation mux to the waveshaping circuitry

and line driver. The transmitter drives the E1 or T1 line from the TTIP/TRING pi

ns through a coupling transformer.

The line driver can handle both CEPT 30/ISDN-PRI lines for E1 and long-haul (CSU) or short-haul (DSX-1) lines for

T1. The configuration and status registers related to the LIU block are shown in the following table:

Functions Page

Global Registers

GCR1 Global Control Register 1 various 151

GTRR Global Transceiver Reset Register LIU reset and soft reset bits 153

GTISR Global Transceiver Interrupt Status Register LIU interrupt status bits (one per port) 154

GTIMR Global Transceiver Interrupt Mask Register LIU interrupt mask bits (one per port) 155

LIU Registers

LTRCR LIU Transmit Rx Control Register E1/T1 mode, LOS criteria, etc. 304

LTISR LIU Transmit Impedance Selection Register Transmit impedance, LBO, 2048kHz 305